Reactivity of BH3 and 9-BBN towards palladium(II) complexes of diphenylvinyl- and diphenylallyl-phosphine; X-ray structures of [PdCl2(PPh2CH2CH2CH 3)]2 and [PdCl2(PPh<

Article abstract of DOI:10.1016/S0022-328X(99)00283-1

Palladium(II) chloride complexes PdCl₂L₂ and [PdCl₂L]₂ have been prepared with the phosphine ligands PPh₂CH=CH₂ and PPh₂CH₂CH=CH₂. The reactions of PdCl

Full text of DOI:10.1016/S0022-328X(99)00283-1

www.elsevier.nl/locate/jorganchem
Journal of Organometallic Chemistry 586 (1999) 234–240
Reactivity of BH3 and 9-BBN towards palladium(II) complexes of
diphenylvinyl- and diphenylallyl-phosphine; X-ray structures of
[PdCl2(PPh2CH2CH2CH3)]2 and [PdCl2(PPh2CH2CHꢀCH2)]2
Simon J. Coles a, Paul Faulds b, Michael B. Hursthouse a, David G. Kelly b,*,
Georgia C. Ranger b, Andrew J. Toner b, Neil M. Walker b
a Department of Chemistry, Uni6ersity of Southampton, Highfield, Southampton, SO17 1BJ, UK
b Department of Chemistry and Materials, Manchester Metropolitan Uni6ersity, Chester Street, Manchester, M1 5GD, UK
Received 8 April 1999
Abstract
Palladium(II) chloride complexes PdCl2L2 and [PdCl2L]2 have been prepared with the phosphine ligands PPh2CHꢀCH2 and
PPh2CH2CHꢀCH2. The reactions of PdCl2L2 complexes with thf·BH3 afford equilibria in which the components may be identified
by 31P{1H}-NMR spectroscopy. PdCl2L2 and [PdCl2L]2 complexes and phosphine–borane adducts are observed. In addition,
analogues of the PdCl2L2 and [PdCl2L]2 complexes are present in which one or both phosphine ligands have undergone alkene
hydroboration. The reaction of PdCl2(PhCN)2 and the cyclic adduct formed between 9-BBN and PPh2CH2CHꢀCH2 [cyclo-(9-
borabicyclo[3.3.1]nonanyl)-propyl(diphenyl)phosphine] has been studied. Opening of the P–B dative bond occurs with the
formation of a [PdCl2L%]2 complex in which the phosphine ligand contains a pendant borane moiety. Hydrolysis in air yields the
crystallographically characterised dimer [PdCl2(PPh2CH2CH2CH3)]2. The X-ray structure of the unsaturated analogue,
[PdCl2(PPh2CH2CHꢀCH2)]2, has also been obtained. Both compounds exist as symmetrical dimeric structures with terminal and
asymmetric bridging halides. © 1999 Elsevier Science S.A. All rights reserved.
Keywords: Phosphine–borane; Hydroboration; Alkenylphosphine; Palladium(II); Borabicyclononane
boration can only be achieved by the addition of a
second equivalent of BH3, whereas intramolecular hy-
droboration occurs with 9-BBN resulting in cyclised
adducts [3]. The present study focuses on the effect of
phosphine complexation on the reactivity of BH3 and
9-BBN towards diphenylvinyl- and diphenylallylphos-
phines. Complexes of palladium(II) chloride were se-
lected for this study as a general class of complexes for
which synthesis, structure and ligand lability are firmly
established [5–8].
1. Introduction
Considerable current interest exists in the resolution
of chiral tertiary phosphines via the formation of phos-
phine–borane adducts [1]. Although many phosphines
may only react with boranes to form adducts, those
possessing additional functionalities can offer alterna-
tive reaction pathways [2]. Moreover, given appropriate
conditions a single borane moiety may react with both
phosphine and a secondary functionality to afford cy-
clised products. The reactivity of v-alkenyldiphenyl-
phosphines towards BH3 and 9-BBN has been investi-
gated for vinyl-, allyl- and butenyl-substituted phosphi-
nes [3]. B–P donor/acceptor formation predominates,
presumably due to the additional stability derived from
the Umpolung [4]. When BH3 is utilised, alkene hydro-
2. Results and discussion
2.1. Synthesis of complexes with diphenyl6inyl- and
diphenylallylphosphine
The chemistry of tertiary phosphine complexes of
palladium(II) has been extensively studied. Within the
* Corresponding author. Fax: +44-161-2476357.
E-mail address: d.g.kelly@mmu.ac.uk (D.G. Kelly)
0022-328X/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved.
PII: S0022-328X(99)00283-1

S.J. Coles et al. / Journal of Organometallic Chemistry 586 (1999) 234–240
235
present work further characterisation of the specific
diphenylvinyl- and diphenylallyl-phosphine complexes
has only been undertaken to provide 31P{1H}-NMR
data necessary for the elucidation of BH3 and 9-BBN
reactivity. Thus, the reported complex PdCl2(PPh2-
CHꢀCH2)2 (1) [8], as well as PdCl2(PPh2CH2CHꢀCH2)2
(2) were prepared by the normal route of reacting two
equivalents of phosphine with PdCl2(PhCN)2. As ex-
pected, both complexes exist as cis and trans isomers in
solution.
The general class of sym-[PdCl2P]2 complexes has
been known since the early studies of Mann et al. [9]
The complexes [PdCl2(PPh2CHꢀCH2)]2 (3) and
[PdCl2(PPh2CH2CHꢀCH2)]2 (4) can be prepared by the
1:1 reaction of PdCl2(PhCN)2 and tertiary phosphine or
by 1:1 reaction of 1 or 2 with PdCl2(PhCN)2. Com-
pound 4 can also be isolated from the reaction of
NiCl2(PPh2CHꢀCH2)2 (5) with two equivalents of
PdCl2(PhCN)2. 31P{1H}-NMR studies suggest that the
modification of reaction stoichiometry in the latter
affords 2 at 1:1 Ni:Pd ratios with no evidence for the
formation of Ni2 or NiPd dimeric species. In contrast
to the very numerous crystallographic characterisations
of PdCl2P2 complexes, those of sym-[PdCl2P]2 com-
pounds are sparse. Hence, the X-ray structure of 4 has
been obtained (Section 2.3).
able ligand combinations. The use of hydroborated
vinyl and allyl derivatives in such studies would be
ideal, however, the preference for phosphine–borane
formation precludes this alternative.
The mechanisms of P-donor exchange [6], anion ex-
change [8] and isomerisation [10] in PdX2P2 have been
examined in numerous publications. The present reac-
tions do not aim to reiterate these studies, aiming
simply to assign the 31P{1H}-NMR resonances of the
specific phosphine complexes relevant to the present
work. Thus 2:1 molar ratios of PPh2CHꢀ
CH2:PPh2CH2CH3 were reacted with PdCl2(PhCN)2 in
a total phosphine:palladium ratio of 2:1. Data for cis
and trans isomers of PdCl2LI2, PdCl2L2II (LI=
PPh2CHꢀCH2; LII=PPh2CH2CH3) correspond to
those reported by Nelson [7] and Grim [5], respectively,
Table 1. Resonances with small upfield or downfield
shifts from the these symmetrical complexes are as-
signed to PdCl2LILII complexes in accord with earlier
studies [6]. 2JPP coupling constants correspond well with
published work [6,11]. Traces of sym-[PdCl2LI]2 and
sym-[PdCl2LII]2 complexes are also observed as
downfield resonances [5,12]. Reactions using LIII
=
PPh2CH2CHꢀCH2 and LIV=PPh2CH2CH2CH3 afford
comparable data; cis and trans isomers of PdCl2LI2II,
PdCl2LI2V and PdCl2LIIILIV, plus sym-[PdCl2LIII]2 and
sym-[PdCl2LIV]2 complexes being observed (Table 1). A
BH3 reactivity studies (Section 2.2) result in incom-
plete hydroboration of the available v-alkenyl function-
2
zero JPP coupling for trans-PdCl2LIIILIV is recorded,
alities.
Consequently,
moderately
complex
this may result from the pseudo-symmetry of the steri-
cally and electronically similar allyl- and propyl-substi-
tuted phosphines or from ligand exchange processes.
One notable feature of this work is that trans-
PdCl2LILII and trans-PdCl2LIIILIV are formed at all,
since Nelson and co-workers reported the formation of
cis-only mixed phosphine complexes of relatively high
thermodynamic stability and kinetic inertness [6]. How-
ever, it must be recognised that the latter involved
phosphine exchange between PdCl2L†2 and PdCl2L2††
31P{1H}-NMR data corresponding to unsaturated and
hydroborated phosphines in a series of environments
are observed. Isomerisation and equilibration renders
the separation of these components impractical. Thus,
to corroborate the assignment of the various species the
31P{1H}-NMR chemical shifts of model systems have
been
obtained
for
comparative
purposes.
PPh2CHꢀCH2/PPh2CH2CH3 and PPh2CH2CHꢀCH2/
PPh2CH2CH2CH3 provide suitable and readily avail-
Table 1
31P{1H}-NMR data for equilibria obtained from the reaction of PdCl2(PhCN)2 with PPh2CHꢀCH2/PPh2CH2CH3 and PPh2CH2CHꢀCH2/
PPh2CH2CH2CH3 mixtures
Complex
31P{1H} l (ppm)
Complex
31P{1H} l (ppm)
LI a
25.7
21.8
LII a
33.8
LIII a
30.3
24.7
LIV a
32.5
Sym-[PdCl2LI]2
Sym-[PdCl2LII]2
Cis-[PdCl2LI2]
Sym-[PdCl2LIII
]
2
Sym-[PdCl2LIV
]
2
Cis-[PdCl2LI2II
Cis-[PdCl2LI2V
Cis-[PdCl2LIILIV
Trans-[PdCl2L2III
Trans-[PdClI2V
Trans-[PdCl2LIIILIV
]
]
Cis-[PdCl2LI2I]
30.0
27.7
Cis-[PdCl2LILII]
Trans-[PdCl2LI2]
Trans-[PdCl2LI2I]
Trans-[PdCl2LILII]
20.9 b
13.6
29.8 b
]
24.1 b
14.9
27.3 b
]
19.0
]
15.9
12.1 c
20.9 c
]
15.1 b
15.5 b
a LI, PPh2CHꢀCH2; LII, PPh2CH2CH3; LIII, PPh2CH2CHꢀCH2; LIV, PPh2CH2CH2CH3.
b 2JPP=0 Hz.
c 2JPP=556 Hz.

236
S.J. Coles et al. / Journal of Organometallic Chemistry 586 (1999) 234–240
complexes (L†, L††=various P donors), rather than
the reaction of tertiary phosphine mixtures with
PdCl2(PhCN)2. Thus, within the two pairs of satu-
rated/unsaturated phosphines used in the present
study rates of PhCN displacement by these phosphi-
nes will be similar. Therefore, the isolation of cis and
trans isomers of both symmetrically and unsymmetri-
cally substituted phosphine complexes is not surpris-
ing.
Table 2
31P{1H}-NMR data for the reaction of 1 with one and four equiva-
lents of thf·BH3
Products
1+1thf·BH3 31P{1H} 1+4thf·BH3 31P{1H}
l (ppm)
l (ppm)
LI a
26.0
21.7
LV a
LI a
25.9
21.0
LV a
Sym-[PdCl2LI]2
Sym-[PdCl2LV]2
Cis-[PdCl2LI2]
Absent
33.8
Cis-[PdCl2LV2 ]
Absent
29.8 b
30.7
2.2. Reacti6ity with BH3 and 9-BBN
Cis-[PdCl2LILV]
Trans-[PdCl2LI2]
Trans-[PdCl2LV2 ]
20.8 b
13.6
20.8 b
13.6
29.7 b
The reactivity of BH3 with vinyl- and allyl-substi-
tuted phosphines has been investigated by Imamoto
[2] and Schmidbaur [3]. Both ligands readily form
phosphine–borane adducts with thf·BH3 in preference
to hydroboration of the alkene function. Moreover,
internal hydroboration and cyclisation does not pro-
ceed even under forcing conditions, although addi-
tional free thf·BH3 does result in alkene
hydroboration. Thus, addition of thf·BH3 to CH2Cl2
and CHCl3 solutions of 1 and 2 offers the potential of
metal reduction, phosphine–borane formation, or
alkene hydroboration. In dilute (millimolar) solutions
of 1 the addition of thf·BH3 produces a series of
31P{1H}-NMR resonances, Table 2. Using one equiva-
lent of thf·BH3 per mole of 1 phosphine abstraction
from 1 to give phosphine–borane is the predominant
reaction; the ligand-deficient palladium fragments
dimerising to 3. There is some evidence for limited
BH3 reactivity with the alkene groups of coordinated
phosphines as evidenced by the assignment of
31P{1H}-NMR resonances to PdCl2LILV (LI=
PPh2CHꢀCH2; LV=PPh2CH2CH2BH2). In view of the
recognised lability of the general class of PdX2P2 com-
plexes, it is perhaps surprising that redistribution of LI
and LV does not occur to afford a mixture of
PdCl2LI2, PdCl2LILV and PdCl2LV2 based on statistical
and thermodynamic factors. However, such exchanges
may not be significant for PdCl2LILV species, since
similar mixed phosphine systems appear relatively in-
ert [6].
Absent
20.9 c
19.2
Trans-[PdCl2LILV] 12.2 c
12.1 b
18.9 d
20.8 b
LIBH3, LVBH3
19.0 d
a LI, PPh2CHꢀCH2; LV, PPh2CH2CH2BH2.
b 2JPP=0 Hz.
c 2JPP=550 Hz.
d Broad.
ligand abstraction to form phosphine–borane is the
principal form of reactivity with alkene hydroboration
being a secondary feature, although in this instance
[PdCl2P]2 species could not be observed by 31P{1H}-
NMR (Table 3). 1:4 Complex:thf·BH3 stoichiometries
result in significantly more phosphine abstract ion and
the clear evidence for the formation of [PdCl2P]2 spe-
cies. Alkene hydroboration is more extensive with
complexes containing both one and two hydroborated
alkenes being observed. When compared with the re-
activity of the vinyl phosphine complex, 1, the hy-
droboration of alkene functionalities in 2 is less
regioselective. For the former the a-PPh2 group
strongly influences BH3 addition at the alkene func-
tion resulting only in PPh2CH2CH2BH2 (LV) forma-
tion. As would be expected, this PPh2 influence is less
significant for the allyl substituted ligand. Although
terminal BH2 addition to afford PPh2(CH2)3BH2 (LVI)
still occurs most readily, there is also evidence for the
presence of species containing PPh2CH2CH(BH2)CH3
(LVII). Identification of these final species must be
considered tentative, since assignments are made by
analogy with the saturated/unsaturated mixed ligand
systems described in Section 2.2.
On reacting four equivalents of thf·BH3 with 1
phosphine abstraction to form phosphine–borane con-
tinues be a significant feature of reactivity. However,
alkene hydroboration becomes more extensive with cis
and trans PdCl2LILV and PdCl2LV2 being observed.
Clearly product distribution is dependant on stoi-
chiometry. There is also evidence for a concentration
dependance; the use of similar reaction stoichiometries
in neat thf·BH3 or the addition of thf·BH3 to 10−1M
CH2Cl2 solutions results in the reduction of 1 to
metallic palladium and the isolation of phosphine–bo-
rane.
Stoichiometric reactions of 9-BBN and 2 proceed in
a similar manner to those of thf·BH3. 31P{1H}-NMR
spectroscopy indicates the presence of unreacted 2, the
dimeric complex 4, a phosphine–borane adduct (9.8
ppm) and the cyclised phosphine–borane adduct 6
(15.4 ppm) (Scheme 1). The isolation of a single palla-
dium complex containing a hydroborated phosphine
again appears to be precluded by the establishment of
equilibria and by the potential for palladium reduction
The reactivity of 2 with thf·BH3 is broadly similar
to that of 1; at 1:1 ratios of complex and thf·BH3

S.J. Coles et al. / Journal of Organometallic Chemistry 586 (1999) 234–240
237
if these equilibria are shifted by the presence of high
borane concentrations. Thus, an alternative reaction
strategy using PdCl2(PhCN)2 and the cyclised adduct 6
was considered; since the latter contains no B–H bond-
ing the potential for metal reduction is removed.
31P{1H}-NMR data are consistent with the facile dis-
placement of PhCN to form PdCl2LV2 III and
[PdCl2LVIII]2 complexes in which ring opening of the
cyclic phosphine–borane, 6, affords the phosphine lig-
and PPh2(CH2)3B(C8H14) (LVIII). Attempts to crystallise
such species were unsuccessful although hydrolysis of
the proposed dimer, [PdCl2LVIII]2, affords the crystallo-
graphically characterised diphenylpropylphosphine
dimer (7). Isolation of such a product in the presence of
moisture accords with the known hydrolytic instability
of hydroborated alkenes and with the insolubility of
dimeric palladium(II) phosphine complexes noted by
Grim and Keiter [5].
contains a single [PdCl2(PPh2CH2CH2CH3)]2 moiety.
Selected bond lengths and angles for the two complexes
are given in Table 4, whilst the two structures are
shown in Figs. 1 and 2, respectively. Despite the early
characterisation of [PdCl2(PBut3)]2 [9] relatively few
comparisons with 4 and 7 have been reported. A more
recent characterisation of [PdCl2(PBut3)]2, plus the X-
ray diffraction study of [PdCl2(PPh3)]2 indicate both
compounds are similar to 4 and 7 [13,14], whilst the
complex [PdI2(PPh2CHꢀCH2)]2 contains generally com-
parable features [12].
3. Experimental
3.1. Crystallographic characterisation
Data collection and structure solution for 4 and 7
were performed using previously described methods;
resulting crystal data are given in Table 5 [15–17].
Crystallographic data for the structural analyses have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC, No. 118821 Compound 4 and
No. 118822 Compound 7. Copies of this information
may be obtained free of charge from The Director,
CCDC, 12, Union Road, Cambridge CB2 1EZ [fax:
+44-1223-336-033 or e-mail deposit@ccdc.cam.ac.uk
or http://www.ccdc.cam.ac.uk].
2.3. Crystallographic characterisation of 4 and 7
Strong structural analogies exist between 4 and 7, the
main chemical difference resulting from the presence of
allyl and propyl phosphine substituents. Both structures
contain centrosymmetric dimeric complexes in which
each palladium exists in square planar geometry formed
from a terminal chloride, a phosphine and two bridging
chlorides. These bridging anions form almost orthogo-
nal bonds to the palladium centres. The bridging Pd–Cl
bond distances in both compounds are asymmetric with
the longer bonds lying opposite the more strongly trans
influencing phosphine ligand. Crystallisation produces
two crystallograhically distinct, but chemically identi-
cal, molecules in the structure of 4. The structure of 7
3.2. Synthesis
Commercial materials (including palladium and
nickel salts, diphenylalkylphosphines, thf·BH3 and 9-
BBN) were used as received. PPh2CHꢀCH2 was pre-
Table 3
31P{1H}-NMR for the reaction of 2 with one and four equivalents of thf·BH3
Products
2+1thf·BH3
LIII a
31P{1H} l (ppm)
2+4thf·BH3
LIII a
31P{1H} l (ppm)
LVI a
LVI a
LVII a
Sym-[PdCl2LIII
]
Absent
24.3
29.8
2
Sym-[PdCl2LVI
]
Absent
32.3
2
Cis-[PdCl2LI2II
Cis-[PdCl2LV2 I
Cis-[PdCl2LIIILVI
Cis-[PdCl2LIIILVII
Trans-[PdCl2L2III
Trans-[PdCl2LV2 I
]
]
24.6
27.4
27.5
]
24.3 b
Absent
14.9
27.0 b
Absent
24.4 b
19.0 b
14.9
27.2 b
]
20.8 b
14.2 b
]
]
15.8
15.8
Trans-[PdCl2LIIILVI
]
15.1 c
15.4 c
Absent
15.1 c
12.5 b
15.9 d
15.4 c
Trans-[PdCl2LIIILVII
]
Absent
LIIIBH3, LVIBH3
15.9 d
a LIII, PPh2CH2CHꢀCH2; LVI, PPh2(CH2)3BH2; LVII, PPh2CH2CH(BH2)CH3.
b 2JPP=0 Hz.
c 2JPP=556 Hz.
d Broad.

238
S.J. Coles et al. / Journal of Organometallic Chemistry 586 (1999) 234–240
Scheme 1. Reactivity of 2 with 9-BBN and of PdCl2(PhCN)2 with 6.
pared by the Grignard route. PPh2CH2CHꢀCH2 was
synthesised by the reaction of CH2CHꢀCH2Br with
[PdCl2(PPh2CHꢀCH2)]2 (3): Elemental analysis for
C14H13Cl2PPd, expected C, 43.1; H, 3.3; found: C,
43.3; H, 3.2. 1H: l=5.54 (dd 3J(HH)=18.7 Hz,
1
LiPPh2. In each case the H- and 31P{1H}-NMR data
(CDCl3 200 and 81 MHz, respectively) were compara-
ble with literature values [18]. Solvents were dried by
conventional methods, and reactions were performed
under nitrogen using standard Schlenk-line techniques
[19]. The following were all synthesised by published
methods; Pd(PhCN)2Cl2 [20], PdCl2(PPh2CHꢀCH2)2 (1)
[7], NiCl2(PPh2CHꢀCH2)2 (5) [21], and cyclo-(9-borabi-
cyclo[3.3.1]nonanyl)-propyl(diphenyl)phosphine (6) [3].
Synthesis of 1–4 was by the following general
method. PdCl2(PhCN)2 (0.4811 g; 1.255 mmol) is
stirred in dry thf under reflux (5 cm3).
Ph2PCH2CHꢀCH2 (0.58 g; 2.6 mmol) is dissolved in a
similar volume of thf. Addition results in the forma-
tion of a yellow–green solution from which 2 precipi-
tates on addition of Et2O (25 cm3) to the cooled thf
solution. The solid is filtered and dried in vacuo before
Table 4
Bond lengths and angles for 4 and 7
Compound 4 a
Compound 7
,
Bonds lengths (A) and
angles (°)
Metal centred
Pd–Cl (terminal)
Pd–P
2.277(2), 2.275(2)
2.2222(2),
2.217(2)
2.420(2), 2.429(2)
2.309(2), 2.321(5)
87.98(7), 92.04(6)
2.2684(7)
2.2275(6)
Pd–Cl (bridging, trans to P)
Pd–Cl (bridging, cis to P)
P–Pd–Cl (terminal)
P–Pd–Cl (bridging, trans to 176.89(7), 176.39(6) 176.36(2)
P)
2.4444(5)
2.3208(6)
90.39(2)
P–Pd–Cl (bridging, cis to P)
Cl–Pd–Cl
94.03(6), 90.85(6)
94.04(6), 93.32(6)
93.14(2)
94.52(2)
Allyl/propyl function
P–C(13)
C(13)–C(14)
recrystallisation from CH2Cl2/Et2O. Yield 0.67
(85%).
g
1.822(6), 1.839(6)
1.451(11),
1.500(9)
1.820(2)
1.518(4)
[PdCl2(PPh2CH2CHꢀCH2)2] (2): Elemental analysis
C(14)–C(15)
1.16(3), b
1.519(4)
for C30H30Cl2P2Pd, expected C, 57.6; H, 5.1; found: C,
1
1.289(10)
57.2; H, 4.8. H (cis/trans not resolved): l=3.37 (m,
P–C(13)–C(14)
C(13)–C(14)–C(15)
114.5(5), b 112.1(5) 115.19(18)
2H, PCH2CHꢀCH2), 4.88 (d, 1H, PCH2CHꢀCH2), 5.02
(m, 1H, PCH2CHꢀCH2), 5.87 (m, 1H, PCH2CHꢀCH2),
7.20–7.72 (m, 10H, Ph2P); 31P{1H} l=24.7 and 14.9
133(2), b 124.6(8)
111.3(3)
a Data for two distinct molecules.
b Disordered site.
(cis:trans 26:74). IR(KBr); w(CꢀC) 1634 (s) cm−1
.

S.J. Coles et al. / Journal of Organometallic Chemistry 586 (1999) 234–240
239
Table 5
Crystal data for 4 and 7
4
7
Colour and habit
Size (mm)
Red block
0.12×0.08×0.07 0.60×0.30×0.20
Red block
Formula
C30H30Cl4P2Pd
7.982(2)
14.089(3)
14.459(3)
96.33(3)
89.86(3)
97.68(3)
1601.5(6)
0.71069
Triclinic
P-1
C15H17Cl2PPd
,
a (A)
11.4519(2)
9.21470(10)
15.6374(3)
,
b (A)
,
c (A)
h (°)
i (°)
k (°)
96.5308(7)
3
,
V (A )
1639.44(5)
0.71069
Monoclinic
P2(1)/c
4
Mo–Kh, u (nm)
System
Space group
Z
2
Collection
FAST TV
Nonius Kap-
paCCD
24 245
Fig. 1. Crystal structure of 4 (showing one of the chemically identical
molecules).
Total reflections
Observed data [I\2|(I)]
2q
Absorption correction
Solution
6724
3542
3103
3
3J(HP)=23.5 Hz, 1H, PCHꢀCHH), 6.18 dd J(HH)=
1.92B2qB25.06 2.84B2qB26.37
3
12.1 Hz, J(HP)=43.6 Hz, 1H, PCHꢀCHH), 7.05 (ddd
DIFFABS
Direct methods
F2 SHELXS-86
Riding
353
0.0402
SORTAV
Direct methods
F2 SHELXS-97
Riding
174
0.0241
3J(HH)=12.1 Hz, 3J(HH)=18.7 Hz, 2J(HP)=23.5
Hz, 1H, PCHꢀCH2), 7.37–7.82 (m, 10H, Ph2P);
31P{1H} l=25.7.
Refinement
Hydrogen atoms
No. of parameters
R1
[PdCl2(PPh2CH2CH=CH2)]2 (4): Elemental analysis
for C15H15Cl2PPd, Expected C, 44.6; H, 3.7; Found: C,
wR2
0.1074
0.0594
1
44.4; H, 4.1. H: l=3.41 (s, 2H, PCH2CHꢀCH2), 4.88
(d 3J(HH)=16.9 Hz, 1H, PCH2CHꢀCHH), 5.02 (d
3J(HH)=9.9 Hz, 1H, PCH2CHꢀCHH), 5.87 (dd
3
3J(HH)=9.9 Hz, J(HH)=16.9 Hz, 1H, PCHꢀCH2),
mixture of PPh2Et (0.1181 g; 0.55 mmol) and
PPh2CHꢀCH2 (0.2109 g; 1.00 mmol) is dissolved in a
similar volume of thf. Addition results in the formation
of a yellow–green solution from which the phosphine
complexes precipitate on addition of Et2O (25 cm3) to
the cooled thf solution. Crude yield, 0.40 g (ca. 85%).
The solid is extracted with CDCl3 to afford a yellow–
orange solution suitable for 31P{1H}-NMR spectro-
scopy.
7.08–7.80 (m, 10H, Ph2P); 31P{1H} l=30.3. IR(KBr);
w(CꢀC) 1634 (s) cm−1
.
3.3. Reaction of PdCl2(PhCN)2 with mixed
alkenyl/alkyl phosphines
The following is typical. PdCl2(PhCN)2 (0.2956 g;
1.54 mmol) is dissolved in thf (5 cm3) under reflux. A
Fig. 2. Crystal structure of 7.

240
S.J. Coles et al. / Journal of Organometallic Chemistry 586 (1999) 234–240
[2] (a) T. Imamoto, T. Oshiki, T. Onozawa, T. Kusumozo, K. Sato,
J. Am. Chem. Soc. 112 (1990) 5244. (b) T. Imamoto, E. Hi-
rakawa, Y. Yamanoi, T. Inoue, K. Yamaguchi, H. Seki, J. Org.
Chem. 60 (1995) 7697.
[3] H. Schmidbaur, M. Sigl, A. Schier, J. Organomet. Chem. 529
(1997) 323.
[4] A.H. Cowley, M.C. Damasco, J. Am. Chem. Soc. 93 (1971)
6815.
[5] S.O. Grim, R.L. Keiter, Inorg. Chim. Acta. 4 (1970) 56.
[6] A.W. Verstuyft, D.A. Redfield, L.W. Cary, J.H. Nelson, Inorg.
Chem. 15 (1976) 1128.
3.4. Reaction of thf·BH3 with 1 and 2, and 9-BBN
with 2
Compound 1 (6.0 mg, 10 mmol) is placed in an
NMR tube containing 2.0 cm3 of dry degassed CDCl3.
thf·BH3 (10 ml, 1 M thf·BH3, 10 mmol) is added and the
sealed tube heated to 60°C for 1 h. 31P{1H}- and
1H-NMR data are obtained upon cooling to ambient
temperature. No significant spectral changes are ob-
served after a further 7 days at ambient temperature.
[7] J.A. Rahn, M.S. Holt, M. O’Neil-Johnson, J.H. Nelson, Inorg.
Chem. 27 (1988) 1316.
[8] J.A. Rahn, M.S. Holt, J.H. Nelson, Polyhedron 8 (1989) 897.
[9] (a) F.G. Mann, D. Purdie, J. Chem. Soc. (1935) 1549. (b) ibid
(1936) 873. (c) F.G. Mann, A.F. Wells, J. Chem. Soc. (1938) 702.
[10] A.W. Verstuyft, L.W. Cary, J.H. Nelson, Inorg. Chem. 15 (1976)
3161 and references therein.
[11] J.G. Verkade, Coord. Chem. Rev. 9 (1973) 1.
[12] N.W. Alcock, W.L. Wilson, J.H. Nelson, Inorg. Chem. 32 (1993)
3193.
[13] P.A. Chaloner, S.Z. Dewa, P.B. Hitchcock, Acta Crystallogr.
Sect. C. 51 (1995) 232.
[14] J. Vicente, M.C. Lagunas, E. Bleuel, M.C. Ramirez de Arellano,
CCDC Ref. 183737 (1997).
[15] J.A. Darr, S.R. Drake, M.B. Hursthouse, K.M.A. Malik, Inorg.
Chem. 32 (1993) 5704.
[16] G.M. Sheldrick, Acta. Crystallogr. Sect. A. 46 (1990) 467.
[17] G.M. Sheldrick, SHELX-93. University of Go¨ttingen, Germany,
1993.
[18] L. Maier, in: L. Maier, G.M. Kosolapoff (Eds.), Organic Phos-
phorus Compounds, vol. 1, Wiley-Interscience, New York, 1972.
Ch. 1 and references therein.
3.5. Reaction of PdCl2(PhCN)2 and 6
Compound 6 (0.190 g, 0.54 mmol) was added to a thf
solution (5 cm3) of PdCl2(PhCN)2 (0.105 g; 0.27 mmol).
The solution changes from yellow to deep red in ca. 10
min. The solvent was removed in vacuo after 1 h and
the solid redissolved in CDCl3 (5 cm3) for NMR analy-
sis. On standing over ca. 7 days deep red crystals of 8
precipitated from solution.
[PdCl2(PPh2CH2CH2CH3)]2 (7): Elemental analysis
for C15H17Cl2PPd, expected C, 44.4; H, 4.2; found: C,
1
43.9; H, 4.3. H: l=0.94 (t, 3H, PCH2CH2CH3), 2.36
(dd,
2H,
PCH2CH2CH3.),
3.48
(dd,
2H,
PCH2CH2CH3.), 7.37–7.81 (m, 10H, Ph2P); 31P{1H}
l=32.3.
[19] S.J. Coles, M.B. Hursthouse, D.G. Kelly, A.J. Toner, N.M.
Walker, J. Organomet. Chem. 580 (1999) 304.
[20] G.K. Anderson, M. Lin, Inorg. Synth. 28 (1990) 61.
[21] S.J. Coles, P. Faulds, M.B. Hursthouse, D.G. Kelly, G.C.
Ranger, N. Walker, J. Chem. Res. (1999), 418 (S), 1811 (M).
References
[1] M. Ohff, J. Holz, M. Quirmbach, A. Borner, Synthesis 10 (1998)
1391.
.
.